In this paper, temperature measurement of axisymmetric dilute hydrogen flame is described using digital laser-speckle technique, which allows the measurement of refractive index field of the flame without any tracers. The measurement system consists of laser and CCD camera, which are placed in-line configuration. The temperature field of the flame is derived from the refractive index field using the cross-correlation analysis of the speckle pattern with and without flame. The influence of the species concentration on the temperature measurement is evaluated from the gas composition in the flame using gas chromatography. It is found that the temperature field measured by the present method with concentration correction agrees with that of the thermocouple measurement within an experimental accuracy, suggesting the usefulness of this measurement technique.

中文翻译：

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用数字激光散斑技术测量稀氢火焰的温度

在本文中，使用数字激光散斑技术描述了轴对称稀氢火焰的温度测量，该技术允许在没有任何示踪剂的情况下测量火焰的折射率场。测量系统由激光和 CCD 相机组成，它们是在线配置的。火焰的温度场是通过对有火焰和无火焰的散斑图案进行互相关分析而从折射率场导出的。使用气相色谱法从火焰中的气体成分评估物质浓度对温度测量的影响。发现本方法测量的温度场与浓度校正在实验精度内与热电偶测量一致，